The present invention relates to a class of compounds wherein 2-nitro-3-phenylbenzofuran is substituted by an acidic group which are active antimicrobial agents, to processes for their use and to intermediates in their preparation.
Compounds wherein 2-nitro-3-phenylbenzofuran is substituted by an alkanoic acid are known and are known to have antimicrobial activity (see, for example, Belgian Pat. No. 846,502 and German Offenlegungsschrift No. P 2642877). However, the known compounds contain only a single alkanoic acid group and it is always substituted on the 3-phenylbenzofuran system. The compounds of the present invention, on the other hand, either include a second alkanoic acid group bonded to the benzo ring or the substituent acidic groups therein are linked by heteroatoms (oxygen or sulfur), are substituted by hydroxy or phenyl, or contain two carboxylic groups.